1 //===- HexagonVectorPrint.cpp - Generate vector printing instructions -----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This pass adds the capability to generate pseudo vector/predicate register
10 // printing instructions. These pseudo instructions should be used with the
11 // simulator, NEVER on hardware.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "Hexagon.h"
16 #include "HexagonInstrInfo.h"
17 #include "HexagonSubtarget.h"
18 #include "llvm/ADT/StringRef.h"
19 #include "llvm/CodeGen/MachineBasicBlock.h"
20 #include "llvm/CodeGen/MachineFunction.h"
21 #include "llvm/CodeGen/MachineFunctionPass.h"
22 #include "llvm/CodeGen/MachineInstr.h"
23 #include "llvm/CodeGen/MachineInstrBuilder.h"
24 #include "llvm/CodeGen/MachineOperand.h"
25 #include "llvm/CodeGen/TargetOpcodes.h"
26 #include "llvm/IR/DebugLoc.h"
27 #include "llvm/IR/InlineAsm.h"
28 #include "llvm/Pass.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/Debug.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/raw_ostream.h"
33 #include <string>
34 #include <vector>
35
36 using namespace llvm;
37
38 #define DEBUG_TYPE "hexagon-vector-print"
39
40 static cl::opt<bool>
41 TraceHexVectorStoresOnly("trace-hex-vector-stores-only", cl::Hidden,
42 cl::desc("Enables tracing of vector stores"));
43
44 namespace {
45
46 class HexagonVectorPrint : public MachineFunctionPass {
47 const HexagonSubtarget *QST = nullptr;
48 const HexagonInstrInfo *QII = nullptr;
49 const HexagonRegisterInfo *QRI = nullptr;
50
51 public:
52 static char ID;
53
HexagonVectorPrint()54 HexagonVectorPrint() : MachineFunctionPass(ID) {}
55
getPassName() const56 StringRef getPassName() const override { return "Hexagon VectorPrint pass"; }
57
58 bool runOnMachineFunction(MachineFunction &Fn) override;
59 };
60
61 } // end anonymous namespace
62
63 char HexagonVectorPrint::ID = 0;
64
isVecReg(unsigned Reg)65 static bool isVecReg(unsigned Reg) {
66 return (Reg >= Hexagon::V0 && Reg <= Hexagon::V31) ||
67 (Reg >= Hexagon::W0 && Reg <= Hexagon::W15) ||
68 (Reg >= Hexagon::WR0 && Reg <= Hexagon::WR15) ||
69 (Reg >= Hexagon::Q0 && Reg <= Hexagon::Q3);
70 }
71
getStringReg(unsigned R)72 static std::string getStringReg(unsigned R) {
73 if (R >= Hexagon::V0 && R <= Hexagon::V31) {
74 static const char* S[] = { "20", "21", "22", "23", "24", "25", "26", "27",
75 "28", "29", "2a", "2b", "2c", "2d", "2e", "2f",
76 "30", "31", "32", "33", "34", "35", "36", "37",
77 "38", "39", "3a", "3b", "3c", "3d", "3e", "3f"};
78 return S[R-Hexagon::V0];
79 }
80 if (R >= Hexagon::Q0 && R <= Hexagon::Q3) {
81 static const char* S[] = { "00", "01", "02", "03"};
82 return S[R-Hexagon::Q0];
83
84 }
85 llvm_unreachable("valid vreg");
86 }
87
addAsmInstr(MachineBasicBlock * MBB,unsigned Reg,MachineBasicBlock::instr_iterator I,const DebugLoc & DL,const HexagonInstrInfo * QII,MachineFunction & Fn)88 static void addAsmInstr(MachineBasicBlock *MBB, unsigned Reg,
89 MachineBasicBlock::instr_iterator I,
90 const DebugLoc &DL, const HexagonInstrInfo *QII,
91 MachineFunction &Fn) {
92 std::string VDescStr = ".long 0x1dffe0" + getStringReg(Reg);
93 const char *cstr = Fn.createExternalSymbolName(VDescStr);
94 unsigned ExtraInfo = InlineAsm::Extra_HasSideEffects;
95 BuildMI(*MBB, I, DL, QII->get(TargetOpcode::INLINEASM))
96 .addExternalSymbol(cstr)
97 .addImm(ExtraInfo);
98 }
99
getInstrVecReg(const MachineInstr & MI,unsigned & Reg)100 static bool getInstrVecReg(const MachineInstr &MI, unsigned &Reg) {
101 if (MI.getNumOperands() < 1) return false;
102 // Vec load or compute.
103 if (MI.getOperand(0).isReg() && MI.getOperand(0).isDef()) {
104 Reg = MI.getOperand(0).getReg();
105 if (isVecReg(Reg))
106 return !TraceHexVectorStoresOnly;
107 }
108 // Vec store.
109 if (MI.mayStore() && MI.getNumOperands() >= 3 && MI.getOperand(2).isReg()) {
110 Reg = MI.getOperand(2).getReg();
111 if (isVecReg(Reg))
112 return true;
113 }
114 // Vec store post increment.
115 if (MI.mayStore() && MI.getNumOperands() >= 4 && MI.getOperand(3).isReg()) {
116 Reg = MI.getOperand(3).getReg();
117 if (isVecReg(Reg))
118 return true;
119 }
120 return false;
121 }
122
runOnMachineFunction(MachineFunction & Fn)123 bool HexagonVectorPrint::runOnMachineFunction(MachineFunction &Fn) {
124 bool Changed = false;
125 QST = &Fn.getSubtarget<HexagonSubtarget>();
126 QRI = QST->getRegisterInfo();
127 QII = QST->getInstrInfo();
128 std::vector<MachineInstr *> VecPrintList;
129 for (auto &MBB : Fn)
130 for (auto &MI : MBB) {
131 if (MI.isBundle()) {
132 MachineBasicBlock::instr_iterator MII = MI.getIterator();
133 for (++MII; MII != MBB.instr_end() && MII->isInsideBundle(); ++MII) {
134 if (MII->getNumOperands() < 1)
135 continue;
136 unsigned Reg = 0;
137 if (getInstrVecReg(*MII, Reg)) {
138 VecPrintList.push_back((&*MII));
139 LLVM_DEBUG(dbgs() << "Found vector reg inside bundle \n";
140 MII->dump());
141 }
142 }
143 } else {
144 unsigned Reg = 0;
145 if (getInstrVecReg(MI, Reg)) {
146 VecPrintList.push_back(&MI);
147 LLVM_DEBUG(dbgs() << "Found vector reg \n"; MI.dump());
148 }
149 }
150 }
151
152 Changed = !VecPrintList.empty();
153 if (!Changed)
154 return Changed;
155
156 for (auto *I : VecPrintList) {
157 DebugLoc DL = I->getDebugLoc();
158 MachineBasicBlock *MBB = I->getParent();
159 LLVM_DEBUG(dbgs() << "Evaluating V MI\n"; I->dump());
160 unsigned Reg = 0;
161 if (!getInstrVecReg(*I, Reg))
162 llvm_unreachable("Need a vector reg");
163 MachineBasicBlock::instr_iterator MII = I->getIterator();
164 if (I->isInsideBundle()) {
165 LLVM_DEBUG(dbgs() << "add to end of bundle\n"; I->dump());
166 while (MBB->instr_end() != MII && MII->isInsideBundle())
167 MII++;
168 } else {
169 LLVM_DEBUG(dbgs() << "add after instruction\n"; I->dump());
170 MII++;
171 }
172 if (MBB->instr_end() == MII)
173 continue;
174
175 if (Reg >= Hexagon::V0 && Reg <= Hexagon::V31) {
176 LLVM_DEBUG(dbgs() << "adding dump for V" << Reg - Hexagon::V0 << '\n');
177 addAsmInstr(MBB, Reg, MII, DL, QII, Fn);
178 } else if (Reg >= Hexagon::W0 && Reg <= Hexagon::W15) {
179 LLVM_DEBUG(dbgs() << "adding dump for W" << Reg - Hexagon::W0 << '\n');
180 addAsmInstr(MBB, Hexagon::V0 + (Reg - Hexagon::W0) * 2 + 1,
181 MII, DL, QII, Fn);
182 addAsmInstr(MBB, Hexagon::V0 + (Reg - Hexagon::W0) * 2,
183 MII, DL, QII, Fn);
184 } else if (Reg >= Hexagon::Q0 && Reg <= Hexagon::Q3) {
185 LLVM_DEBUG(dbgs() << "adding dump for Q" << Reg - Hexagon::Q0 << '\n');
186 addAsmInstr(MBB, Reg, MII, DL, QII, Fn);
187 } else
188 llvm_unreachable("Bad Vector reg");
189 }
190 return Changed;
191 }
192
193 //===----------------------------------------------------------------------===//
194 // Public Constructor Functions
195 //===----------------------------------------------------------------------===//
196 INITIALIZE_PASS(HexagonVectorPrint, "hexagon-vector-print",
197 "Hexagon VectorPrint pass", false, false)
198
createHexagonVectorPrint()199 FunctionPass *llvm::createHexagonVectorPrint() {
200 return new HexagonVectorPrint();
201 }
202